diff --git a/tests/conftest.py b/tests/conftest.py
new file mode 100644
index 00000000..e7a3da6b
--- /dev/null
+++ b/tests/conftest.py
@@ -0,0 +1,10 @@
+def pytest_configure(config):
+    import sys
+
+    sys._called_from_test = True
+
+
+def pytest_unconfigure(config):
+    import sys
+
+    del sys._called_from_test